This invention relates to the construction of posts, and more particularly to posts with bases that are buried in the ground.
Wooden posts, for example those used in the construction of fences, are desirable in the construction of fences and the like. Typically, such posts are buried in the ground to a depth sufficient to provide the requisite stability. However, posts buried in the ground can suffer from the detrimental effects of moisture, decay, rotting, and pests (such as termites), which cause deterioration and shorten the useful lifespan of wooden posts. Further, posts buried in the ground may be susceptible to frost heave, which can cause posts to become loosened or dislodged.
The invention, in one aspect, features a post base having an upwardly-tapering portion that is at least partially surrounded by a shell. Preferably, this base also includes a non-tapering portion adjacent to and axially below the upwardly-tapering portion.
In another aspect, the invention features a post base having an upwardly-tapering upper portion and a non-tapered lower portion.
A post, for example, a wooden post, may be attached to the base. Preferably, the post is attached by a rod received within openings in the post and in the upwardly-tapering portion of the base. Preferably, the rod is connected with an adhesive, although friction fit with fasteners, such as, screws, bolts, rivets, threads, interlocking members, or the like, may also be used.
The upwardly-tapering portion may have any suitable tapering profile, for example it may be frustum-shaped, pyramidal, conical, or have curved sides that are either concave or convex. However, the upwardly-tapering portion may have non-tapering or downwardly-tapering sections. The upwardly-tapering portion and the non-tapering portion may have a uniform cross-sectional shape throughout its extent, or it may combine several different shapes. The upwardly-tapering portion and the non-tapering portion may have cross-sectional shapes that are the same or different. For example, the upwardly-tapering portion and/or the non-tapering portion may have cross-sectional shapes that are rounded, ovoid, circular, triangular, quadrilateral, rectangular, square, or have any number of sides.
Preferably, the base includes a shield that projects laterally and/or downwardly from the base. The shield helps to deter termites and other pests.
The base may comprise a massive material such as concrete. In embodiments that include both an upwardly tapering upper portion and a non-tapering lower portion, both the upwardly-tapering portion and the non-tapering portion may include massive material. Preferably, the base comprises a shell having both tapering and non-tapering portions wherein only the tapering portion is filled with massive material, while the non-tapering portion is not so filled. In this way, the post base may be relatively lighter, so that it is easier for an installer to lift and handle the base. Even when the non-tapering portion is not filled with massive material, it nevertheless provides structural stability when the base is buried in the ground. Preferably, the shell contains inward projections that may be connected to indentations in a massive member or in the material held within the shell. Preferably, the indentations are formed by contours in the shell, so that the shell has a uniform thickness throughout. This design simplifies the construction if the shell is made, for example, by injection molding of a plastic. The contours may be either rounded or angled. Alternately, the indentations may comprise baffles or ribs that protrude inwardly from the shell.
Embodiments of the invention may include one or more of the following advantages.
The device provides a solid and secure foundation for the attachment of posts. The tapering shape of the device anchors it firmly in the ground and helps the base to resist frost heave. Using a pipe with predetermined dimensions within the base provides a good fit between the base and a connecting member, such as a rod. Embodiments in which the shell extends around the top of the upper portion and/or the bottom of the lower portion have additional strength and rigidity. The shell may be constructed by injection molding of a plastic.
The device is durable. The device resists rotting, moisture, and the other detrimental effects of the subterranean environment, thereby helping to preserve the post attached to the base. The shield helps to protect the post from termites and other pests. The shield may include a spacer that increases the distance between the post and the remainder of the base. The shell protects concrete or other massive material contained therein. Constructing the base with a shell also provides a uniform configuration for bases. The device can be light enough for installers to lift and handle, but still provide sufficient support for a post. Indentations in the shell help to hold massive material, for example concrete, securely.
Using the device reduces lumber costs. Fence, lamp, and mailbox posts must be buried to a depth sufficient to provide the required stability. Posts having a suitable length may be expensive, difficult to obtain in adequate supply, and difficult to transport. Using the invention obviates the need to bury a portion of a wooden post in the ground, thus reducing the length of wooden posts needed for a particular construction task.
Because posts are attached to the top of the device, which projects above ground level, the device permits replacement of damaged posts without removing the more environment-resistant base from the ground.
The shell may be manufactured in any desired color. For example, the shell may match the color of the post, or the ground. The shell may be white, green, or an earth tone. The shield may also be manufactured in any color. Designs in which only the shield protrudes above the surface of the ground when in use simplify manufacturing, because only the shield need be made in the desired colors, while the remainder of the device may be made without consideration to color. Manufacture of the shell may be simplified by designing the shell walls to have a uniform thickness.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.